Gentrax 12v 100ah LFP look alike

67HR · Senior Member

Gentrax 12v 100ah LFP look alike

valiant81 · Guru

Hi; I went through the same process when i had to upgrade my own batteries in our caravn for a lithium replacement when my agm's died. One other thing to check on is how you want to recharge your new lithium batteries. Does your mains powered battery charger have a lithium profile?? A smart shunt ( current bridge ) is a must with a lithium battery as the old voltage meter is no good with lithium as the terminal voltage will stay at around 13.6 volts for a fully charged battery and 12.8 volts for a lithium battery that is around 20 % capacity left so only a 0.8 volts difference and this is the reason why a good shunt that will give you a guage of capacity that is left.

The other thing is to check on warrentee. Some lithium batteries will only have 12 months, others will have longer and around 3 years is normal, while others lithium batteries will have 5+ years ( these also are a lot more exspencive as well ). There are lithium batteries that the cells are graded. A cells, B cells, C cells and it depends on the quality of the materials and how the batteries are manufactured in the first place. Some cells are as you stated " pouch cells" while others are what is called " prismatic cells". It apears that the prismatic cells are the one to go for.

If you want to recharge your lithium batteries from your aulternator you will also need a DC to DC charger to recharge your lithium battery or risk of your aulternator failing. All of this upgeading will cost a penny or two, but worth it in the end as lithium is a real game changer over agm batteries.

-- Edited by valiant81 on Sunday 25th of August 2024 02:34:37 PM

Whenarewethere · Guru

valiant81 wrote:
A cells, B cells, C cells and it depends on the quality of the materials and how the batteries are manufactured in the first place.

Cheap batteries will be C cells.

Will cost you more in the long run.

67HR · Senior Member

Thanks for the replys, it mainly is for a battery box on the road which I have a dc-dc charger with mppt built in.

I have future proofed the van by installing a Victron 240-12v charger and I have a Victron shunt to look after my 120ah AGM I keep an eye on them with the Victron app.

TimTim · Guru

Hi 67HR,

The battery you are looking at is more than likely the same as the Gentrax and the same as may others on the internet. They just have different labels on depending on who they are supplying to.

From what I have seen on Ebay I would not trust the so called feedback even though I have posted negative feedback on products. I recently discovered one seller of a product selling under numerous names. That is not to say that there arent good sellers out there as I generally have no issues.

The product you are looking at is probably the lowest of the low and would more than likely contain secondhand or inferior cells which will degrade within a short period of time. Ignore the warranty as in most cases it will be a dogfight in attempting to get anything back plus your return postage costs will be far more than what they pay for postage.

People will say you get what you paid for but that is not always the case. Many expensive batteries will have the same cells as some lower cost ones. Then again an expensive battery may have degraded cells.

https://www.youtube.com/watch?v=9NHTNCK2KUU

A good few people have the VoltX batteries and have no issues with them. Aldi have been selling them and so have Bunnings and Bunnings are great for warranty returns. But note that in the link below they are not actually sold by Bunnings.

https://www.bunnings.com.au/voltx-12v-100ah-lifepo4-lithium-battery-prismatic-cells-rv-camping-power_p0587428?

I build my own batteries so I have no personal experience of them expect for what people have posted but if looking at purchasing then they would be top of my list For an inexpensive battery.

Here is a teardown of one.

https://www.youtube.com/watch?v=MGrgYqF_PUQ

Good luck

Tim

-- Edited by TimTim on Monday 26th of August 2024 09:47:52 AM

-- Edited by TimTim on Monday 26th of August 2024 09:53:17 AM

-- Edited by TimTim on Monday 26th of August 2024 10:11:23 AM

67HR · Senior Member

TimTim wrote:
Hi 67HR,
The battery you are looking at is more than likely the same as the Gentrax and the same as may others on the internet. They just have different labels on depending on who they are supplying to.
From what I have seen on Ebay I would not trust the so called feedback even though I have posted negative feedback on products. I recently discovered one seller of a product selling under numerous names. That is not to say that there arent good sellers out there as I generally have no issues.
The product you are looking at is probably the lowest of the low and would more than likely contain secondhand or inferior cells which will degrade within a short period of time. Ignore the warranty as in most cases it will be a dogfight in attempting to get anything back plus your return postage costs will be far more than what they pay for postage.
People will say you get what you paid for but that is not always the case. Many expensive batteries will have the same cells as some lower cost ones. Then again an expensive battery may have degraded cells.
https://www.youtube.com/watch?v=9NHTNCK2KUU
A good few people have the VoltX batteries and have no issues with them. Aldi have been selling them and so have Bunnings and Bunnings are great for warranty returns. But note that in the link below they are not actually sold by Bunnings.
https://www.bunnings.com.au/voltx-12v-100ah-lifepo4-lithium-battery-prismatic-cells-rv-camping-power_p0587428?
I build my own batteries so I have no personal experience of them expect for what people have posted but If I was to look at purchasing then they would be top of my list For an inexpensive battery.
Good luck
Tim

-- Edited by TimTim on Monday 26th of August 2024 09:47:52 AM

-- Edited by TimTim on Monday 26th of August 2024 09:53:17 AM

Thanks for the time to post Tim, and your advice.

It was interesting to note that when I replied to the seller saying I wouldn't purchase due to the battery having pouch cells they suggested the voltx brand that has prismatic cells.

I may look at building a battery myself down the track and used EVE cells and a Daly BMS. As this guy has https://www.youtube.com/watch?v=4z8mwkLX1dc&t=6s

At this stage I may look at the voltex from The Green shed as I was unaware they sold them (as a buy in).

Here's the advice from the ebay seller. Who I was impressed with their speed of reply and help.

Thanks Again,

Regards Trev

Dick0 · Guru

Hi Trevor, I have 3 x 135AH Voltrax LiFePO4 purchased from Outbax on Ebay.

Then they sold Voltx LiFePO4. Now they sell Gentrax LiFePO4. They all have the same specs.

Probably all come from same factory in China. Have had mine for four years and are all round perfect.

Experts here will rubbish these batteries. There are good review videos on these types of batteries on Youtube by people in the know, who would have greater review experience than many here.

As I have said, they work perfectly for me being charged by MPPT solar charger.

Review on Gentrax:

Gentrax 200ah 12v lithium battery (youtube.com)

-- Edited by Dick0 on Monday 26th of August 2024 10:43:38 AM

-- Edited by Dick0 on Monday 26th of August 2024 11:01:26 AM

valiant81 · Guru

Hi 67HR; with your DC to DC charger, does it have the correct profile for charging lithium batteries. The reason i asked is when i upgraded mt own caravan i removed the DC to DC charger as it did not have a profile to suit lithium.

67HR · Senior Member

valiant81 wrote:
Hi 67HR; with your DC to DC charger, does it have the correct profile for charging lithium batteries. The reason i asked is when i upgraded mt own caravan i removed the DC to DC charger as it did not have a profile to suit lithium.

Thanks Stephen,

It sure does.

Dick0 · Guru

valiant81 wrote:
Hi 67HR; with your DC to DC charger, does it have the correct profile for charging lithium batteries. The reason i asked is when i upgraded mt own caravan i removed the DC to DC charger as it did not have a profile to suit lithium.

Absolutely, I did the same and replaced with appropriate LiFePO4 dc>dc charger.

TimTim · Guru

Hi Trev,

Whist many may not agree with how he constructs battery in the video, the one thing he fails to do is top balance the cells. A minor voltage different in cells that are not fully charged can be substantial when charged up. Google Will Prowse videos or Off-grid garage.

You also need to be aware of which buyers to avoid when buying cells so just ask on here if u need help.

Good luck

Tim

-- Edited by TimTim on Thursday 29th of August 2024 12:21:55 AM

67HR · Senior Member

Thanks Tim, I'll check out top balancing.

Trev.

67HR · Senior Member

I ended up buying one of these https://www.ebay.com.au/itm/156283987550?mkcid=16&mkevt=1&mkrid=705-154756-20017-0&ssspo=ZK4yBHERR9e&sssrc=4429486&ssuid=rhK41mpDSFO&var=&widget_ver=artemis&media=COPY

A grade cells (whether new or not) and paid $231 with coupon.

As I said I want it to run my Waeco 35 from a battery box.

I'm away for another 10 days or so, so will divulge more when I get home and test it..

If I get 2 or 3 years out of ill be happy as I will have paid no more than an a AGM.

-- Edited by 67HR on Monday 16th of September 2024 05:16:53 PM

TimTim · Guru

Hi Trevor,

Well I hope it works out for you. I did post last week about Woolworths having 100Ah VoltX batteries on special for $289 but it has finished now. I bought one to test and after two discharge and recharge tests both confirmed 107Ah capacity.

Tim

67HR · Senior Member

TimTim wrote:
Hi Trevor,
Well I hope it works out for you. I did post last week about Woolworths having 100Ah VoltX batteries on special for $289 but it has finished now. I bought one to test and after two discharge and recharge tests both confirmed 107Ah capacity.
Tim

Hi Tim, thanks, I'm sure I committed a day before your post.

I had watched a couple of voltX tear downs but was confused as to what battery was what. It seems voltX have different grades on their batteries. I believe that 100ah LFP's price point has dropped a lot as 200ah are becoming the norm. It will interesting to see what it delivers.